Discovery of an Earth-like exoplanet in the habitable zone – Interview with Vigneshwaran Krishnamurthy

In this artist’s concept, Gliese 12 b is shown retaining a thin atmosphere. It could also have a very thick atmosphere similar to that of Venus, or no atmosphere at all. Credit: NASA/JPL-Caltech/R. Hurt (Caltech-IPAC).

Vigneshwaran Krishnamurthy a Postdoctoral researcher at McGill University with the Trottier Institute for Research on Exoplanets (IREx), played a key role in a recent study revealing the existence of Gliese 12 b, an Earth-sized planet orbiting a low-mass star. Although this planet about the same size as Earth it is located very close to its star.

This discovery is exciting because it’s one of the few small planets around cool stars that we can study in detail. This gives us a chance to learn more about rocky planets beyond our Solar System.

Here, he answers our questions about this fascinating planet.

IREx: Can you tell us about Gliese 12 b? How was it discovered?

Vigneshwaran: Gliese 12 b was first spotted by the Transiting Exoplanet Survey Satellite (TESS) space telescope, which looks for tiny dips in a star’s brightness when a planet passes in front of it. Then, ground-based telescopes and instruments followed up with more observations, like transit photometry and radial velocity measurements, to confirm it’s a planet and learn more about its properties.

IREx: What is special about it? Is there any evidence of life on this exoplanet?

Vigneshwaran: Gliese 12 b is special because it’s similar in size to Earth and orbits a nearby star, making it easier to study. It also sits just inside the star’s habitable zone, where conditions might be right for liquid water. However, it’s likely very hot, and scientists are eager to learn more about whether it has an atmosphere, and what that atmosphere might be like.

There’s no evidence of life on Gliese 12 b yet. While it might be too hot for life as we know it, studying its atmosphere will help us understand what conditions exist on rocky planets around other stars.

IREx: This was probably a huge team effort, what role did you play?

Subaru Telescope on top of Maunakea. Credit: Subaru Telescope.

Vigneshwaran: I contributed by observing with the Subaru telescope, collecting crucial data that helped confirm the planet’s existence. My role also involved analyzing this data and understanding how the planet interacts with its star. It’s always exciting to collaborate with scientists around the world on such groundbreaking discoveries!

IREx: What are the next steps for this research?

Vigneshwaran: Next, we hope to use the James Webb Space Telescope to study Gliese 12 b’s atmosphere in more detail. This will help us understand if the planet has an atmosphere, and also if it contains water, clouds, or other gases. We also want to measure its mass more precisely to learn about its composition, like if it’s rocky or has more gas.

IREx: What draws you to projects like this?

Vigneshwaran: I’ve always been fascinated by space and the possibility of finding other planets like Earth. These projects let us explore big questions, like how planets form and whether they can support life. It’s exciting to push the boundaries of what we know and imagine what might be out there beyond our Solar System!

IREx: Why should the public care about this topic?

Vigneshwaran: Studying exoplanets like Gliese 12 b helps us understand our place in the universe. By learning how other planets form and evolve, we also learn more about Earth and its future. These discoveries inspire curiosity, push science and technology forward, and remind us that there’s so much more to explore!